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%I #14 Nov 21 2013 12:48:16
%S 3,5,7,11,17,19,23,29,31,41,43,47,59,71,79,83,101,103,107,131,137,139,
%T 149,163,167,179,191,197,199,211,223,227,239,251,263,269,271,281,311,
%U 331,347,359,379,383,419,431,443,461,463,467,479,491,499,503,521,523
%N Primes of the form p*q - p - q, where p and q are primes.
%C Some primes have no unique representation (besides of symmetry in p,q!), e.g. 11 with (p,q)=(2,13) and (3,7).
%H T. D. Noe, <a href="/A091305/b091305.txt">Table of n, a(n) for n=1..1000</a>
%e 31 is a member with p=3, q=17.
%t mp[{p_,q_}]:=p*q-p-q; Take[Union[Select[mp/@Subsets[Prime[Range[100]],{2}], PrimeQ]],60] (* _Harvey P. Dale_, Nov 27 2011 *)
%o (PARI) isA091305(p)=fordiv(p++,d,if(isprime(d+1)&isprime(p/d+1), return(isprime(p-1)))) \\ _Charles R Greathouse IV_, Feb 15 2011
%Y Primes of the form p*q + p + q: A066938. Primes of the form p*q + p - q: A091301.
%K easy,nice,nonn
%O 1,1
%A _Zak Seidov_, Feb 21 2004
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